Aircraft: B737
Phase of flight: Climb
Anomaly: Aircraft Equipment Problem Less Severe; Flight Deck / Cabin / Aircraft Event Other / Unknown

Right after push back and completing our demo we were walking to the back galley right around the aft lavs; when the B Flight Attendant (FA) asked if we could smell fuel. We nodded in agreement and went to our jumpseats. Right after take-off the B and I; the C FA noted the R2 door was making a lot of noise; but a different kind of noise then we sometimes hear when the door is trying to seal with the pressurization. This was a loud gushing of air.Finally; it was so loud and our ears were popping that even though we were under 10;000 feet we agreed we needed to contact the flight deck to let them know what we were experiencing with the R2 door. I later found out this was right around 8;000 feet. The flight deck stated they had no signs of this issue and asked me if it was something we could deal with or if we needed to turn around. I stated we needed to turn around as this noise was extremely loud and our ears were popping. They asked if this was the D flight attendant. I said no; and stated my name. They then stated they wanted a 2nd opinion; even though the C FA who was sitting right next to me was in agreement with me. The A FA headed back. When she got in the aft galley she called the Flight Deck (FD) and let them know that she could faintly hear the noise before Row 21; but at Row 21 it became extremely loud and this was not normal pressurization. I later found out we went to 14;000 feet before the FD realized we did need to turn back. We then were told they were going to have to circle around a bit to burn off fuel. We sat in our jumpsuit for a while; until our ears couldn't take the loud noise anymore and I had a raging headache. At this time we let the flight deck know we couldn't sit in the jumpseats any longer. As advised; the B briefed the exit rows on emergency procedures and to not open the windows upon landing even if they see fire trucks as they are there for precaution because we were going to have to do a heavy landing; unless they hear over the PA to evacuate. We moved two passengers (and made sure to brief them) to the exits rows to accommodate us taking their seats in the back of the plane. At this time; I remember debating how much time we had and if I should put on some oxygen on myself and the B FA. But I figured we would be landing soon. Finally; the FD made an announcement that we were turning back. Everything was down played. The loud gushing continued until we were on the ground.Upon arrival at the gate; every door was kept shut except for L1 so maintenance could come on board and check doors from the inside and outside before opening. A female passenger in row 28 I believe came back asking for a diet coke; stating she almost threw up on descent and felt yucky to the point that she wondered if she was suffering another stroke and went through the stroke signs in her head. The B FA gave her water and I called upfront and asked for medics to come evaluate her. No one else came to us with symptoms. I believe that is because we down played the whole event in order to not panic anyone; no one really knew exactly why we were turning around.Later; we found out that Fire Department and or [medical consultants] should have been called by [customer service] for the woman; not airport police. Airport police came with a jumpkit to evaluate her; but not being paramedics were not fully knowledgeable in treating her and her symptoms. By this point the B and I were both experiencing extreme fatigue. Her ear wouldn't clear and called crew scheduling to be taking off the trip that was now going to be around a 13 hour day with the delays starting with a 4am shift. We were never given the option to be taken off the trip. I was experiencing an extreme headache; overwhelming fatigue and felt foggy and disconnected mentally. It wasn't until our supervisor called me and I couldn't remember her name; that I realized something wasn't right with me. I called scheduling to be released. The B and I went to theER due to the pressurization issue as we seemed to be exhibiting signs of hypoxia and symptoms from the pressurization problem of R2 door. Two juice caps were later found in the R2 door seal. This is why we smelled jet fuel on taxi out and the loud continuous noise and the pressurization issues of R2 from take-off to landing. This is the 2nd time in my career that I have experienced a pressurization issue with R2. This is also the 2nd time the Flight Deck has advised me that they didn't show indications that there was a pressurization issue and didn't believe us for a while. I do believe there needs to be an indicator located in the back of the plane near our galley where we spend extend amounts of time. I am not sure how the juice lids ended up in the door. One can speculate. I am assuming they were buried underneath the slide and somehow upon opening/cracking R2 to remove the garbage can; they didn't fall out but wedged in-between. Unless this door was completely opened then they would have fallen out. I wish the flight deck would have stopped climbing when we alerted them to the problem instead of climbing to 14;000 while waiting for a 3rd opinion and not spent so much time in the air with this issue; as I believe it made our symptoms worse. Looking back; we should have moved out of the aft jumpseats sooner; but we were trying to follow protocol; until we couldn't handle the situation any longer. We also didn't know it would take half an hour till we were back on the ground. Also; [customer service] should have known to call the Fire Department and [medical consultants] for that passenger; but I believe she was new. We should have been given the option to be removed from the flight after dealing with a pressurization issue; as we were no longer fit to fly; instead of having to call in sick to crew scheduling. A B737-900 Flight Attendant seated by the R2 door for takeoff; experienced a loud rushing air noise around the door as the aircraft climbed after takeoff. Eventually the flight returned to the departure airport. Maintenance found two plastic caps from juice containers preventing the door seal from functioning properly.